Leave a wide trail in both word and deed.
Encourage movement. We’ve noticed that on the days he doesn’t want to do more than sit in his chair and play with the up and down buttons, his balance is a little off and his short term memory is worse. Thankfully, the weather is improving and we’ve had a couple of very nice days where he’s been willing to spend some time outside and walk around the neighborhood. He does enjoy that and there have been days he’s set a fairly fast pace to keep up with.